BOSTON — During the seven weeks of his trial, James “Whitey” Bulger has been called a murderer, drug dealer and, most galling to the former Boston mob boss, a “rat,” for informing the FBI about other criminal gangs so he could operate with impunity.

On Tuesday, Bulger’s former right-hand man hit the 83-year-old defendant with another accusation: “pedophilia.”

Stephen “The Rifleman” Flemmi, who testified that Bulger killed his step-daughter, was being cross-examined about his sexual relationship with the woman 22 years younger than him. After Bulger’s attorney asked him whether he was a pedophile, Flemmi cracked and said his ex-boss also had a relationship with a substantially younger girl.

“You want to talk about pedophilia, right over there at that table,” Flemmi said, pointing to Bulger. “He had a young girlfriend, 16 years old, he took to Mexico.”

Bulger, who was partners in crime with Flemmi for 20 years, faces the possibility of life in prison if convicted on charges related to 19 murders he is accused of committing or ordering in the 1970s and ’80s while running the Winter Hill gang.

The gangster, whose story inspired the 2006 Academy Award-winning film “The Departed,” has pleaded not guilty to all charges, although his attorney has admitted Bulger was a drug dealer, extortionist and loan shark, in other words an “organized criminal.”

On Monday, Flemmi testified that Bulger strangled his stepdaughter, 26-year-old Deborah Hussey, after convincing Flemmi that the woman was a threat to the gang. Described as a drug user, Hussey had taken to hanging out at a bar the gang’s members frequented and using Flemmi’s name to gain favors.

Flemmi, now 79 and serving life in prison for 10 murders he confessed to a decade ago, acknowledged he began a sexual relationship with Hussey when she was 18 years old and he was 40, which Hussey later “blurted out” to her mother, Flemmi’s girlfriend.

Stepdaughter killed

Flemmi said he at first was reluctant to help kill the girl. He paid for her rehab and sent her to California and Florida, hoping to get her away from the Boston crime scene.

“I didn’t kill her but I agreed with it, yes, to go along with it,” Flemmi said. “There’s never any justification for murder … I agreed because I was coerced into it.”

Defense attorney Henry Brennan asked Flemmi about testimony from a prior witness that Bulger’s attempt to kill Hussey had failed and Flemmi finished the job with a rope. Flemmi denied the charge that he strangled his stepdaughter.

Last week, Flemmi testified that Bulger also strangled a girlfriend of Flemmi’s who Bulger feared might reveal their relationship with the FBI.

Prosecutors are expected to wrap their case in the coming days, turning the proceedings over to the defense.

Prosecutors say Bulger gave a corrupt FBI agent from his Irish-American neighborhood information about the Italian Mafia, and that the agent in turn turned a blind eye to Bulger’s criminal activity. Bulger and his lawyers have vigorously denied the contention that he ever was an informant.

Witnesses at the trial have recalled an era when Bulger and his cronies routinely shook down bookies, drug dealers and business owners, threatening them with machine guns and burying victims in basements of houses and along the shore.

Bulger fled after a 1994 tip from the corrupt FBI agent that arrest was imminent. He remained on the lam for 16 years, many of them listed prominently on the FBI’s “Most Wanted” list of fugitives, before agents caught up to him living in a seaside Santa Monica, California, apartment with a cache of guns and more than $800,000 in cash.

Jack Nicholson played a character loosely based on Bulger in “The Departed.”